Comparative Pharmacology
Head-to-head clinical analysis: SYNALGOS DC A versus ULTRAM ER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SYNALGOS DC A versus ULTRAM ER.
SYNALGOS-DC-A vs ULTRAM ER
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
SYNALGOS-DC-A contains dihydrocodeine, which is a semisynthetic opioid agonist; aspirin, a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes; and caffeine, a central nervous system stimulant. Dihydrocodeine binds to mu-opioid receptors in the central nervous system to produce analgesia. Aspirin irreversibly acetylates COX-1 and COX-2, reducing prostaglandin synthesis. Caffeine enhances analgesia via adenosine receptor antagonism and possibly by increasing drug absorption.
Tramadol is a centrally acting synthetic opioid analgesic that binds to μ-opioid receptors and inhibits serotonin and norepinephrine reuptake.
1-2 capsules orally every 4-6 hours as needed for pain; each capsule contains dihydrocodeine bitartrate 16 mg, acetaminophen 356.4 mg, and caffeine 30 mg.
100 mg orally once daily initially, titrate up to 100 mg twice daily as needed; maximum 200 mg/day.
None Documented
None Documented
Propoxyphene: 6-12 hours; norpropoxyphene: 30-36 hours; clinical context: prolonged with hepatic impairment, age >60 years, and renal dysfunction; accumulation of norpropoxyphene may cause cardiotoxicity
The terminal elimination half-life of tramadol is approximately 6.3 hours (range 5-9 hours), while its active metabolite M1 has a half-life of about 7.4 hours. Clinically, this supports dosing every 24 hours for the extended-release formulation.
Renal: ~70-80% as free and conjugated propoxyphene; norpropoxyphene is renally eliminated; biliary: 10-20%; fecal: <10%
Renal excretion of tramadol and its metabolites accounts for approximately 90% of total elimination. About 10% is excreted unchanged, 30% as O-desmethyltramadol (M1), and the remainder as other minor metabolites. Biliary/fecal excretion is minimal (<10%).
Category C
Category C
Opioid Analgesic
Opioid Analgesic